<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<meta name="viewport" content="width=device-width, initial-scale=1">
		<title>
			my web site
		</title>
		<style type="text/css">
			body,ul,li{
				margin: 0;
				padding: 0;
			}
			ul,li{
				list-style: none;
			}
			.nav{
				width: 800px;
				height: 40px;
				background: pink;
				margin:  20px auto;
			}
			.nav ul li{
				float: left;
			}
			.nav ul li a{
				display: inline-block;
				height: 40px;
				font: 14px/40px 微软雅黑;
				/* margin: 0 20px; */
				padding: 0 20px;
				text-decoration: none;
			}
			.nav ul li a:hover{
				background: #aaa;
			}
		</style>
	</head>
	<body>
		<div class="nav">
			<ul>
				<li><a href="#">百度</a></li>
				<li><a href="#">百度一下</a></li>
				<li><a href="#">呵呵</a></li>
			</ul>
		</div>
	</body>
</html>